The Mechanisms to Improve Creep Resistance in a Die-Cast MgREMnAl Alloy

• Published in: Magnesium Technology 2023 pp. 143 - 150
• Main Authors: Dong, Xixi, Feng, Lingyun, Nyberg, Eric A., Ji, Shouxun
• Format: Book Chapter
• Language: English
• Published: Cham Springer Nature Switzerland
• Series: The Minerals, Metals & Materials Series
• Subjects: Creep resistance; High pressure die casting; Magnesium alloys; Mechanical properties; Strengthening mechanism
• ISBN: 3031226445; 9783031226441
• ISSN: 2367-1181; 2367-1696
• DOI: 10.1007/978-3-031-22645-8_29

High-pressure die-cast magnesium (Mg) alloys are required for components working at temperatures above 200 °C. These new alloys are necessary for high-volume applications such as critical parts used for internal combustion (IC) engines in power tools. Here we present new developments of a Mg–RE die-cast alloy that shows excellent ambient and high-temperature tensile strength, creep resistanceCreep resistance, stiffness, and thermal conductivity, which are key advantages for alloys used at elevated temperatures. The excellent creep resistanceCreep resistance of the die-cast Mg3.5RE (La, Ce, Nd)1.5GdMnAl alloy, in comparison with its counterpart alloy without the Al addition, shows a significant improvement of the steady-state creep rate (SCR) at 300 °C/50 MPa. The synergistic effect of Al, Gd, and Mn has been found to induce a novel and thermally stable AlMnGd ternary short-range order (SRO, 0–2 nm)/cluster (2–10 nm) in the Mg matrix, which is believed to be responsible for the improvement in creep performance.